點解上課前要講Good mornin Mrs.??? or Miss.???

Good morning Mrs / Miss
因為係禮貌, 尊敬你的老師

Good bye and thank you Mrs
係多謝佢教完你, 獲益良多

I think this is a failure of hk education.
It keeps a distance b/w student and teacher.
And I think the rule is telling me how to react with my teacher...
stupid!